<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style type="text/css">
			body{font-size:30px;}
			#outer-box{
				/* 父元素行高为45px */
				line-height:150%;
				background-color:red;
				color:white;
			}
			#inner-box{
				/* 子元素行高为45px(继承父元素的行高) */
				font-size:20px;
				background-color:purple;
				color:white;
			}
		</style>
	</head>
	<body>
		<div id="outer-box">这是父元素
			<div id="inner-box">这是子元素</div>
		</div>
	</body>
</html>
